Below:

Next story in South and Central Asia

UNITED NATIONS — Myanmar's pro-democracy leader Aung San Suu Kyi has been hospitalized with severe diarrhea, activists with contacts in the country said Friday.

Suu Kyi, 60, was taken to the hospital Thursday afternoon after calling her physician to say she was suffering from diarrhea and weakness, said Thaung Htun, the New York-based U.N. representative for the Burmese government in exile. Myanmar is also known as Burma.

Htun said Suu Kyi, a Nobel Peace Prize winner who has spent much of the last 16 years under house arrest, was delayed going to the hospital because her physician had trouble getting permission to see her.

"The physician should have a visit any time he thinks it's necessary," Htun said. "Delays should not happen because of asking permission from the authorities."

Htun said colleagues in Myanmar had confirmed Suu Kyi's hospitalization. It was not immediately clear whether she had been released.

Washington calls for her releaseIn Washington, the State Department said it had heard reports of Suu Kyi's hospitalization but could not confirm them.

"We would call upon the Burmese government to provide Aung San Suu Kyi any and all medical assistance that she might need and to do so expeditiously and to ensure her safety during any treatment," spokesman Sean McCormack said.

"And we would also reiterate our call on the regime to release her from house arrest. It's sometimes difficult to get good, solid information in Burma, just because of the nature of the place. But we are quite concerned about the reports."

Britain's Foreign Office also expressed concern.

"We've heard reports, we're very concerned about them but we're not able to confirm anything yet," a spokesman for the British Foreign Office said, speaking on condition of anonymity in keeping with government policy.

Junta refuses to yield powerMyanmar's junta took power in 1988 after crushing vast pro-democracy demonstrations in Myanmar. In 1990, it refused to hand over power when Suu Kyi's party won a general election by a landslide.

The United States and many Western nations have since shunned the junta due to its poor human rights record and failure to give up power.

Earlier Friday, the government acknowledged for the first time that it had extended her house arrest last month.